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 * #%L
 * HAPI FHIR JPA Model
 * %%
 * Copyright (C) 2014 - 2024 Smile CDR, Inc.
 * %%
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * #L%
 */
package ca.uhn.fhir.jpa.model.config;

import com.google.common.annotations.VisibleForTesting;
import org.apache.commons.collections4.CollectionUtils;
import org.hl7.fhir.dstu2.model.Subscription;

import java.util.Collections;
import java.util.HashSet;
import java.util.Set;

import static org.apache.commons.lang3.StringUtils.isNotBlank;

public abstract class BaseSubscriptionSettings {
        public static final String DEFAULT_EMAIL_FROM_ADDRESS = "noreply@unknown.com";
        public static final String DEFAULT_WEBSOCKET_CONTEXT_PATH = "/websocket";
        public static final String DEFAULT_RESTHOOK_ENDPOINTURL_VALIDATION_REGEX =
                        "((((http?|https?)://))([-%()_.!~*';/?:@&=+$,A-Za-z0-9])+)";

        private final Set<Subscription.SubscriptionChannelType> mySupportedSubscriptionTypes = new HashSet<>();
        private String myEmailFromAddress = DEFAULT_EMAIL_FROM_ADDRESS;
        private String myWebsocketContextPath = DEFAULT_WEBSOCKET_CONTEXT_PATH;
        private boolean myQualifySubscriptionMatchingChannelName = true;
        private boolean myCrossPartitionSubscriptionEnabled = true;
        private boolean myEnableInMemorySubscriptionMatching = true;
        private boolean myTriggerSubscriptionsForNonVersioningChanges;

        /**
         * @since 6.8.0
         * Prevents any non IN-MEMORY Search params from being created by users.
         */
        private boolean myAllowOnlyInMemorySubscriptions = false;

        /**
         * @since 7.6.0
         *
         * Regex To perform validation on the endpoint URL for Subscription of type RESTHOOK.
         */
        private String myRestHookEndpointUrlValidationRegex = DEFAULT_RESTHOOK_ENDPOINTURL_VALIDATION_REGEX;

        /**
         * This setting indicates which subscription channel types are supported by the server.  Any subscriptions submitted
         * to the server matching these types will be activated.
         */
        public void addSupportedSubscriptionType(Subscription.SubscriptionChannelType theSubscriptionChannelType) {
                mySupportedSubscriptionTypes.add(theSubscriptionChannelType);
        }

        /**
         * This setting indicates which subscription channel types are supported by the server.  Any subscriptions submitted
         * to the server matching these types will be activated.
         */
        public Set<Subscription.SubscriptionChannelType> getSupportedSubscriptionTypes() {
                return Collections.unmodifiableSet(mySupportedSubscriptionTypes);
        }

        /**
         * Indicate whether a subscription channel type is supported by this server.
         *
         * @return true if at least one subscription channel type is supported by this server false otherwise.
         */
        public boolean hasSupportedSubscriptionTypes() {
                return CollectionUtils.isNotEmpty(mySupportedSubscriptionTypes);
        }

        @VisibleForTesting
        public void clearSupportedSubscriptionTypesForUnitTest() {
                mySupportedSubscriptionTypes.clear();
        }

        /**
         * If e-mail subscriptions are supported, the From address used when sending e-mails
         */
        public String getEmailFromAddress() {
                return myEmailFromAddress;
        }

        /**
         * Set the from address used for sending emails when using email subscriptions
         */
        public void setEmailFromAddress(String theEmailFromAddress) {
                myEmailFromAddress = theEmailFromAddress;
        }

        /**
         * If websocket subscriptions are enabled, this specifies the context path that listens to them.  Default value "/websocket".
         */
        public String getWebsocketContextPath() {
                return myWebsocketContextPath;
        }

        /**
         * Set the websocket endpoint context path to use when websocket subscriptions are enabled.  Default value "/websocket".
         */
        public void setWebsocketContextPath(String theWebsocketContextPath) {
                myWebsocketContextPath = theWebsocketContextPath;
        }

        /**
         * This setting returns whether the channel name should be qualified or not.
         *
         * @return whether the channel name is qualified or not
         * @since 6.4.0
         */
        public boolean isQualifySubscriptionMatchingChannelName() {
                return myQualifySubscriptionMatchingChannelName;
        }

        /**
         * This setting controls whether the channel name
         * should be qualified or not.
         * Default is true, ie, the channel name will be qualified.
         *
         * @since 6.4.0
         */
        public void setQualifySubscriptionMatchingChannelName(boolean theQualifySubscriptionMatchingChannelName) {
                myQualifySubscriptionMatchingChannelName = theQualifySubscriptionMatchingChannelName;
        }

        /**
         * If enabled, the server will support cross-partition subscription.
         * This subscription will be the responsible for all the requests from all the partitions on this server.
         * For example, if the server has 3 partitions, P1, P2, P3
         * The subscription will live in the DEFAULT partition. Resource posted to DEFAULT, P1, P2, and P3 will trigger this subscription.
         * <p>
         * Default is <code>false</code>
         * </p>
         *
         * @since 5.7.0
         */
        public boolean isCrossPartitionSubscriptionEnabled() {
                return myCrossPartitionSubscriptionEnabled;
        }

        /**
         * If enabled, the server will support cross-partition subscription.
         * This subscription will be the responsible for all the requests from all the partitions on this server.
         * For example, if the server has 3 partitions, P1, P2, P3
         * The subscription will live in the DEFAULT partition. Resource posted to DEFAULT, P1, P2, and P3 will trigger this subscription.
         * <p>
         * Default is <code>false</code>
         * </p>
         *
         * @since 5.7.0
         */
        public void setCrossPartitionSubscriptionEnabled(boolean theAllowCrossPartitionSubscription) {
                myCrossPartitionSubscriptionEnabled = theAllowCrossPartitionSubscription;
        }
        /**
         * If set to true, the server will prevent the creation of Subscriptions which cannot be evaluated IN-MEMORY. This can improve
         * overall server performance.
         *
         * @since 6.8.0
         */
        public void setOnlyAllowInMemorySubscriptions(boolean theAllowOnlyInMemorySearchParams) {
                myAllowOnlyInMemorySubscriptions = theAllowOnlyInMemorySearchParams;
        }

        /**
         * If set to true, the server will prevent the creation of Subscriptions which cannot be evaluated IN-MEMORY. This can improve
         * overall server performance.
         *
         * @since 6.8.0
         * @return Returns the value of {@link #setOnlyAllowInMemorySubscriptions(boolean)}
         */
        public boolean isOnlyAllowInMemorySubscriptions() {
                return myAllowOnlyInMemorySubscriptions;
        }

        /**
         * If set to <code>false</code> (default is true) the server will not use
         * in-memory subscription searching and instead use the database matcher for all subscription
         * criteria matching.
         * <p>
         * When there are subscriptions registered
         * on the server, the default behaviour is to compare the changed resource to the
         * subscription criteria directly in-memory without going out to the database.
         * Certain types of subscription criteria, e.g. chained references of queries with
         * qualifiers or prefixes, are not supported by the in-memory matcher and will fall back
         * to a database matcher.
         * <p>
         * The database matcher performs a query against the
         * database by prepending ?id=XYZ to the subscription criteria where XYZ is the id of the changed entity
         *
         * @since 3.6.1
         */
        public boolean isEnableInMemorySubscriptionMatching() {
                return myEnableInMemorySubscriptionMatching;
        }

        /**
         * If set to <code>false</code> (default is true) the server will not use
         * in-memory subscription searching and instead use the database matcher for all subscription
         * criteria matching.
         * <p>
         * When there are subscriptions registered
         * on the server, the default behaviour is to compare the changed resource to the
         * subscription criteria directly in-memory without going out to the database.
         * Certain types of subscription criteria, e.g. chained references of queries with
         * qualifiers or prefixes, are not supported by the in-memory matcher and will fall back
         * to a database matcher.
         * <p>
         * The database matcher performs a query against the
         * database by prepending ?id=XYZ to the subscription criteria where XYZ is the id of the changed entity
         *
         * @since 3.6.1
         */
        public void setEnableInMemorySubscriptionMatching(boolean theEnableInMemorySubscriptionMatching) {
                myEnableInMemorySubscriptionMatching = theEnableInMemorySubscriptionMatching;
        }

        /**
         * If set to true (default is false) then subscriptions will be triggered for resource updates even if they
         * do not trigger a new version (e.g. $meta-add and $meta-delete).
         *
         * @since 5.5.0
         */
        public boolean isTriggerSubscriptionsForNonVersioningChanges() {
                return myTriggerSubscriptionsForNonVersioningChanges;
        }

        /**
         * If set to true (default is false) then subscriptions will be triggered for resource updates even if they
         * do not trigger a new version (e.g. $meta-add and $meta-delete).
         *
         * @since 5.5.0
         */
        public void setTriggerSubscriptionsForNonVersioningChanges(boolean theTriggerSubscriptionsForNonVersioningChanges) {
                myTriggerSubscriptionsForNonVersioningChanges = theTriggerSubscriptionsForNonVersioningChanges;
        }

        /**
         * Provides the regex expression to perform endpoint URL validation If rest-hook subscriptions are supported.
         * Default value is {@link #DEFAULT_RESTHOOK_ENDPOINTURL_VALIDATION_REGEX}.
         * @since 7.6.0
         */
        public String getRestHookEndpointUrlValidationRegex() {
                return myRestHookEndpointUrlValidationRegex;
        }

        /**
         * Configure the regex expression that will be used to validate the endpoint URL.
         * Set to NULL or EMPTY for no endpoint URL validation.
         *
         * @since 7.6.0
         */
        public void setRestHookEndpointUrlValidationRegex(String theRestHookEndpointUrlValidationgRegex) {
                myRestHookEndpointUrlValidationRegex = theRestHookEndpointUrlValidationgRegex;
        }

        /**
         * Whether an endpoint validation Regex was set for URL validation.
         *
         * @since 7.6.0
         */
        public boolean hasRestHookEndpointUrlValidationRegex() {
                return isNotBlank(myRestHookEndpointUrlValidationRegex);
        }
}